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-rw-r--r--libguile/fports.c756
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diff --git a/libguile/fports.c b/libguile/fports.c
new file mode 100644
index 000000000..9aa2ea963
--- /dev/null
+++ b/libguile/fports.c
@@ -0,0 +1,756 @@
+/* Copyright 1995-2004,2006-2015,2017-2018
+ Free Software Foundation, Inc.
+
+ This file is part of Guile.
+
+ Guile is free software: you can redistribute it and/or modify it
+ under the terms of the GNU Lesser General Public License as published
+ by the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ Guile is distributed in the hope that it will be useful, but WITHOUT
+ ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+ License for more details.
+
+ You should have received a copy of the GNU Lesser General Public
+ License along with Guile. If not, see
+ <https://www.gnu.org/licenses/>. */
+
+
+
+#define _LARGEFILE64_SOURCE /* ask for stat64 etc */
+#define _GNU_SOURCE /* ask for LONG_LONG_MAX/LONG_LONG_MIN */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+#include <stdio.h>
+#include <fcntl.h>
+
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#include <unistd.h>
+#ifdef HAVE_IO_H
+#include <io.h>
+#endif
+#ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
+#include <sys/stat.h>
+#endif
+#include <poll.h>
+#include <errno.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/select.h>
+#include <full-write.h>
+
+#include "async.h"
+#include "boolean.h"
+#include "dynwind.h"
+#include "extensions.h"
+#include "fdes-finalizers.h"
+#include "filesys.h"
+#include "fluids.h"
+#include "gc.h"
+#include "gsubr.h"
+#include "hashtab.h"
+#include "keywords.h"
+#include "modules.h"
+#include "numbers.h"
+#include "pairs.h"
+#include "ports-internal.h"
+#include "posix.h"
+#include "read.h"
+#include "strings.h"
+#include "symbols.h"
+#include "syscalls.h"
+#include "variable.h"
+#include "version.h"
+
+#include "fports.h"
+
+
+#if SIZEOF_OFF_T == SIZEOF_INT
+#define OFF_T_MAX INT_MAX
+#define OFF_T_MIN INT_MIN
+#elif SIZEOF_OFF_T == SIZEOF_LONG
+#define OFF_T_MAX LONG_MAX
+#define OFF_T_MIN LONG_MIN
+#elif SIZEOF_OFF_T == SIZEOF_LONG_LONG
+#define OFF_T_MAX LONG_LONG_MAX
+#define OFF_T_MIN LONG_LONG_MIN
+#else
+#error Oops, unknown OFF_T size
+#endif
+
+scm_t_port_type *scm_file_port_type;
+
+
+/* Move ports with the specified file descriptor to new descriptors,
+ * resetting the revealed count to 0.
+ */
+static void
+scm_i_evict_port (void *closure, SCM port)
+{
+ int fd = * (int*) closure;
+
+ if (SCM_OPFPORTP (port))
+ {
+ scm_t_fport *fp = SCM_FSTREAM (port);
+ if ((fp != NULL) && (fp->fdes == fd))
+ {
+ fp->fdes = dup (fd);
+ if (fp->fdes == -1)
+ scm_syserror ("scm_evict_ports");
+ scm_set_port_revealed_x (port, scm_from_int (0));
+ }
+ }
+}
+
+void
+scm_evict_ports (int fd)
+{
+ scm_c_port_for_each (scm_i_evict_port, (void *) &fd);
+}
+
+
+SCM_DEFINE (scm_file_port_p, "file-port?", 1, 0, 0,
+ (SCM obj),
+ "Determine whether @var{obj} is a port that is related to a file.")
+#define FUNC_NAME s_scm_file_port_p
+{
+ return scm_from_bool (SCM_FPORTP (obj));
+}
+#undef FUNC_NAME
+
+
+static SCM sys_file_port_name_canonicalization;
+static SCM sym_relative;
+static SCM sym_absolute;
+
+static SCM
+fport_canonicalize_filename (SCM filename)
+{
+ SCM mode = scm_fluid_ref (sys_file_port_name_canonicalization);
+
+ if (!scm_is_string (filename))
+ {
+ return filename;
+ }
+ else if (scm_is_eq (mode, sym_relative))
+ {
+ SCM path, rel;
+
+ path = scm_variable_ref (scm_c_module_lookup (scm_the_root_module (),
+ "%load-path"));
+ rel = scm_i_relativize_path (filename, path);
+
+ return scm_is_true (rel) ? rel : filename;
+ }
+ else if (scm_is_eq (mode, sym_absolute))
+ {
+ char *str, *canon;
+
+ str = scm_to_locale_string (filename);
+ canon = canonicalize_file_name (str);
+ free (str);
+
+ return canon ? scm_take_locale_string (canon) : filename;
+ }
+ else
+ {
+ return filename;
+ }
+}
+
+int
+scm_i_mode_to_open_flags (SCM mode, int *is_binary, const char *FUNC_NAME)
+{
+ int flags = 0;
+ const char *md, *ptr;
+
+ if (SCM_UNLIKELY (!scm_is_string (mode)))
+ scm_out_of_range (FUNC_NAME, mode);
+
+ if (SCM_UNLIKELY (!scm_i_try_narrow_string (mode)))
+ scm_out_of_range (FUNC_NAME, mode);
+
+ md = scm_i_string_chars (mode);
+ *is_binary = 0;
+
+ switch (*md)
+ {
+ case 'r':
+ flags |= O_RDONLY;
+ break;
+ case 'w':
+ flags |= O_WRONLY | O_CREAT | O_TRUNC;
+ break;
+ case 'a':
+ flags |= O_WRONLY | O_CREAT | O_APPEND;
+ break;
+ default:
+ scm_out_of_range (FUNC_NAME, mode);
+ }
+ ptr = md + 1;
+ while (*ptr != '\0')
+ {
+ switch (*ptr)
+ {
+ case '+':
+ flags = (flags & ~(O_RDONLY | O_WRONLY)) | O_RDWR;
+ break;
+ case 'b':
+ *is_binary = 1;
+#if defined (O_BINARY)
+ flags |= O_BINARY;
+#endif
+ break;
+ case '0': /* unbuffered: handled later. */
+ case 'l': /* line buffered: handled during output. */
+ break;
+ default:
+ scm_out_of_range (FUNC_NAME, mode);
+ }
+ ptr++;
+ }
+
+ return flags;
+}
+
+/* scm_open_file_with_encoding
+ Return a new port open on a given file.
+
+ The mode string must match the pattern: [rwa+]** which
+ is interpreted in the usual unix way.
+
+ Unless binary mode is requested, the character encoding of the new
+ port is determined as follows: First, if GUESS_ENCODING is true,
+ 'file-encoding' is used to guess the encoding of the file. If
+ GUESS_ENCODING is false or if 'file-encoding' fails, ENCODING is used
+ unless it is also false. As a last resort, the default port encoding
+ is used. It is an error to pass a non-false GUESS_ENCODING or
+ ENCODING if binary mode is requested.
+
+ Return the new port. */
+SCM
+scm_open_file_with_encoding (SCM filename, SCM mode,
+ SCM guess_encoding, SCM encoding)
+#define FUNC_NAME "open-file"
+{
+ SCM port;
+ int fdes, flags, binary = 0;
+ unsigned int retries;
+ char *file;
+
+ if (SCM_UNLIKELY (!(scm_is_false (encoding) || scm_is_string (encoding))))
+ scm_wrong_type_arg_msg (FUNC_NAME, 0, encoding,
+ "encoding to be string or false");
+
+ scm_dynwind_begin (0);
+
+ file = scm_to_locale_string (filename);
+ scm_dynwind_free (file);
+
+ flags = scm_i_mode_to_open_flags (mode, &binary, FUNC_NAME);
+
+ for (retries = 0, fdes = -1;
+ fdes < 0 && retries < 2;
+ retries++)
+ {
+ SCM_SYSCALL (fdes = open_or_open64 (file, flags, 0666));
+ if (fdes == -1)
+ {
+ int en = errno;
+
+ if (en == EMFILE && retries == 0)
+ /* Run the GC in case it collects open file ports that are no
+ longer referenced. */
+ scm_i_gc (FUNC_NAME);
+ else
+ SCM_SYSERROR_MSG ("~A: ~S",
+ scm_cons (scm_strerror (scm_from_int (en)),
+ scm_cons (filename, SCM_EOL)), en);
+ }
+ }
+
+ /* Create a port from this file descriptor. The port's encoding is initially
+ %default-port-encoding. */
+ port = scm_i_fdes_to_port (fdes, scm_i_mode_bits (mode),
+ fport_canonicalize_filename (filename),
+ 0);
+
+ if (binary)
+ {
+ if (scm_is_true (encoding))
+ scm_misc_error (FUNC_NAME,
+ "Encoding specified on a binary port",
+ scm_list_1 (encoding));
+ if (scm_is_true (guess_encoding))
+ scm_misc_error (FUNC_NAME,
+ "Request to guess encoding on a binary port",
+ SCM_EOL);
+
+ /* Use the binary-friendly ISO-8859-1 encoding. */
+ scm_i_set_port_encoding_x (port, NULL);
+ }
+ else
+ {
+ char *enc = NULL;
+
+ if (scm_is_true (guess_encoding))
+ {
+ if (SCM_INPUT_PORT_P (port))
+ enc = scm_i_scan_for_encoding (port);
+ else
+ scm_misc_error (FUNC_NAME,
+ "Request to guess encoding on an output-only port",
+ SCM_EOL);
+ }
+
+ if (!enc && scm_is_true (encoding))
+ {
+ char *buf = scm_to_latin1_string (encoding);
+ enc = scm_gc_strdup (buf, "encoding");
+ free (buf);
+ }
+
+ if (enc)
+ scm_i_set_port_encoding_x (port, enc);
+ }
+
+ scm_dynwind_end ();
+
+ return port;
+}
+#undef FUNC_NAME
+
+SCM
+scm_open_file (SCM filename, SCM mode)
+{
+ return scm_open_file_with_encoding (filename, mode, SCM_BOOL_F, SCM_BOOL_F);
+}
+
+/* We can't define these using SCM_KEYWORD, because keywords have not
+ yet been initialized when scm_init_fports is called. */
+static SCM k_guess_encoding = SCM_UNDEFINED;
+static SCM k_encoding = SCM_UNDEFINED;
+
+SCM_INTERNAL SCM scm_i_open_file (SCM, SCM, SCM);
+
+SCM_DEFINE (scm_i_open_file, "open-file", 2, 0, 1,
+ (SCM filename, SCM mode, SCM keyword_args),
+ "Open the file whose name is @var{filename}, and return a port\n"
+ "representing that file. The attributes of the port are\n"
+ "determined by the @var{mode} string. The way in which this is\n"
+ "interpreted is similar to C stdio. The first character must be\n"
+ "one of the following:\n"
+ "@table @samp\n"
+ "@item r\n"
+ "Open an existing file for input.\n"
+ "@item w\n"
+ "Open a file for output, creating it if it doesn't already exist\n"
+ "or removing its contents if it does.\n"
+ "@item a\n"
+ "Open a file for output, creating it if it doesn't already\n"
+ "exist. All writes to the port will go to the end of the file.\n"
+ "The \"append mode\" can be turned off while the port is in use\n"
+ "@pxref{Ports and File Descriptors, fcntl}\n"
+ "@end table\n"
+ "The following additional characters can be appended:\n"
+ "@table @samp\n"
+ "@item b\n"
+ "Open the underlying file in binary mode, if supported by the system.\n"
+ "Also, open the file using the binary-compatible character encoding\n"
+ "\"ISO-8859-1\", ignoring the default port encoding.\n"
+ "@item +\n"
+ "Open the port for both input and output. E.g., @code{r+}: open\n"
+ "an existing file for both input and output.\n"
+ "@item 0\n"
+ "Create an \"unbuffered\" port. In this case input and output\n"
+ "operations are passed directly to the underlying port\n"
+ "implementation without additional buffering. This is likely to\n"
+ "slow down I/O operations. The buffering mode can be changed\n"
+ "while a port is in use @pxref{Ports and File Descriptors,\n"
+ "setvbuf}\n"
+ "@item l\n"
+ "Add line-buffering to the port. The port output buffer will be\n"
+ "automatically flushed whenever a newline character is written.\n"
+ "@end table\n"
+ "In theory we could create read/write ports which were buffered\n"
+ "in one direction only. However this isn't included in the\n"
+ "current interfaces. If a file cannot be opened with the access\n"
+ "requested, @code{open-file} throws an exception.")
+#define FUNC_NAME s_scm_i_open_file
+{
+ SCM encoding = SCM_BOOL_F;
+ SCM guess_encoding = SCM_BOOL_F;
+
+ scm_c_bind_keyword_arguments (FUNC_NAME, keyword_args, 0,
+ k_guess_encoding, &guess_encoding,
+ k_encoding, &encoding,
+ SCM_UNDEFINED);
+
+ return scm_open_file_with_encoding (filename, mode,
+ guess_encoding, encoding);
+}
+#undef FUNC_NAME
+
+
+/* Building Guile ports from a file descriptor. */
+
+/* Build a Scheme port from an open file descriptor `fdes'.
+ MODE indicates whether FILE is open for reading or writing; it uses
+ the same notation as open-file's second argument.
+ NAME is a string to be used as the port's filename.
+*/
+SCM
+scm_i_fdes_to_port (int fdes, long mode_bits, SCM name, unsigned options)
+#define FUNC_NAME "scm_fdes_to_port"
+{
+ SCM port;
+ scm_t_fport *fp;
+
+ if (options & SCM_FPORT_OPTION_VERIFY)
+ {
+ /* Check that the foreign FD is valid and matches the mode
+ bits. */
+#ifdef F_GETFL
+ int flags = fcntl (fdes, F_GETFL, 0);
+ if (flags == -1)
+ SCM_SYSERROR;
+ flags &= O_ACCMODE;
+ if (flags != O_RDWR
+ && ((flags != O_WRONLY && (mode_bits & SCM_WRTNG))
+ || (flags != O_RDONLY && (mode_bits & SCM_RDNG))))
+ {
+ SCM_MISC_ERROR ("requested file mode not available on fdes",
+ SCM_EOL);
+ }
+#else
+ /* If we don't have F_GETFL, as on mingw, at least we can test that
+ it is a valid file descriptor. */
+ struct stat st;
+ if (fstat (fdes, &st) != 0)
+ SCM_SYSERROR;
+#endif
+ }
+
+ fp = (scm_t_fport *) scm_gc_malloc_pointerless (sizeof (scm_t_fport),
+ "file port");
+ fp->fdes = fdes;
+ fp->options = options;
+
+ port = scm_c_make_port (scm_file_port_type, mode_bits, (scm_t_bits)fp);
+
+ SCM_SET_FILENAME (port, name);
+
+ return port;
+}
+#undef FUNC_NAME
+
+SCM
+scm_fdes_to_port (int fdes, char *mode, SCM name)
+{
+ return scm_i_fdes_to_port (fdes, scm_mode_bits (mode), name,
+ SCM_FPORT_OPTION_VERIFY);
+}
+
+/* Return a lower bound on the number of bytes available for input. */
+static int
+fport_input_waiting (SCM port)
+{
+ int fdes = SCM_FSTREAM (port)->fdes;
+
+ struct pollfd pollfd = { fdes, POLLIN, 0 };
+
+ if (poll (&pollfd, 1, 0) < 0)
+ scm_syserror ("fport_input_waiting");
+
+ return pollfd.revents & POLLIN ? 1 : 0;
+}
+
+
+
+
+/* Revealed counts --- an oddity inherited from SCSH. */
+
+#define SCM_REVEALED(x) (SCM_FSTREAM(x)->revealed)
+
+
+/* Find a port in the table and return its revealed count.
+ Also used by the garbage collector.
+ */
+int
+scm_revealed_count (SCM port)
+{
+ return SCM_REVEALED (port);
+}
+
+SCM_DEFINE (scm_port_revealed, "port-revealed", 1, 0, 0,
+ (SCM port),
+ "Return the revealed count for @var{port}.")
+#define FUNC_NAME s_scm_port_revealed
+{
+ port = SCM_COERCE_OUTPORT (port);
+ SCM_VALIDATE_OPFPORT (1, port);
+ return scm_from_int (scm_revealed_count (port));
+}
+#undef FUNC_NAME
+
+/* Set the revealed count for a port. */
+SCM_DEFINE (scm_set_port_revealed_x, "set-port-revealed!", 2, 0, 0,
+ (SCM port, SCM rcount),
+ "Sets the revealed count for a port to a given value.\n"
+ "The return value is unspecified.")
+#define FUNC_NAME s_scm_set_port_revealed_x
+{
+ int r;
+
+ port = SCM_COERCE_OUTPORT (port);
+ SCM_VALIDATE_OPFPORT (1, port);
+
+ r = scm_to_int (rcount);
+ SCM_REVEALED (port) = r;
+
+ return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+/* Set the revealed count for a port. */
+SCM_DEFINE (scm_adjust_port_revealed_x, "adjust-port-revealed!", 2, 0, 0,
+ (SCM port, SCM addend),
+ "Add @var{addend} to the revealed count of @var{port}.\n"
+ "The return value is unspecified.")
+#define FUNC_NAME s_scm_adjust_port_revealed_x
+{
+ int a;
+
+ port = SCM_COERCE_OUTPORT (port);
+ SCM_VALIDATE_OPFPORT (1, port);
+
+ a = scm_to_int (addend);
+ SCM_REVEALED (port) += a;
+
+ return SCM_UNSPECIFIED;
+}
+#undef FUNC_NAME
+
+
+
+static int
+fport_print (SCM exp, SCM port, scm_print_state *pstate SCM_UNUSED)
+{
+ scm_puts ("#<", port);
+ scm_print_port_mode (exp, port);
+ if (SCM_OPFPORTP (exp))
+ {
+ int fdes;
+ SCM name = SCM_FILENAME (exp);
+ if (scm_is_string (name) || scm_is_symbol (name))
+ scm_display (name, port);
+ else
+ scm_puts (SCM_PORT_TYPE (exp)->name, port);
+ scm_putc (' ', port);
+ fdes = (SCM_FSTREAM (exp))->fdes;
+
+#if (defined HAVE_TTYNAME) && (defined HAVE_POSIX)
+ if (isatty (fdes))
+ scm_display (scm_ttyname (exp), port);
+ else
+#endif /* HAVE_TTYNAME */
+ scm_intprint (fdes, 10, port);
+ }
+ else
+ {
+ scm_puts (SCM_PORT_TYPE (exp)->name, port);
+ scm_putc (' ', port);
+ scm_uintprint ((scm_t_bits) SCM_PORT (exp), 16, port);
+ }
+ scm_putc ('>', port);
+ return 1;
+}
+
+/* fill a port's read-buffer with a single read. returns the first
+ char or EOF if end of file. */
+static size_t
+fport_read (SCM port, SCM dst, size_t start, size_t count)
+{
+ scm_t_fport *fp = SCM_FSTREAM (port);
+ signed char *ptr = SCM_BYTEVECTOR_CONTENTS (dst) + start;
+ ssize_t ret;
+
+ retry:
+ ret = read (fp->fdes, ptr, count);
+ if (ret < 0)
+ {
+ if (errno == EINTR)
+ {
+ scm_async_tick ();
+ goto retry;
+ }
+ if (errno == EWOULDBLOCK || errno == EAGAIN)
+ return -1;
+ scm_syserror ("fport_read");
+ }
+ return ret;
+}
+
+static size_t
+fport_write (SCM port, SCM src, size_t start, size_t count)
+{
+ int fd = SCM_FPORT_FDES (port);
+ signed char *ptr = SCM_BYTEVECTOR_CONTENTS (src) + start;
+ ssize_t ret;
+
+ retry:
+ ret = write (fd, ptr, count);
+ if (ret < 0)
+ {
+ if (errno == EINTR)
+ {
+ scm_async_tick ();
+ goto retry;
+ }
+ if (errno == EWOULDBLOCK || errno == EAGAIN)
+ return -1;
+ scm_syserror ("fport_write");
+ }
+
+ return ret;
+}
+
+static scm_t_off
+fport_seek (SCM port, scm_t_off offset, int whence)
+{
+ scm_t_fport *fp = SCM_FSTREAM (port);
+ off_t_or_off64_t result;
+
+ result = lseek_or_lseek64 (fp->fdes, offset, whence);
+
+ if (result == -1)
+ scm_syserror ("fport_seek");
+
+ return result;
+}
+
+static void
+fport_truncate (SCM port, scm_t_off length)
+{
+ scm_t_fport *fp = SCM_FSTREAM (port);
+
+ if (ftruncate (fp->fdes, length) == -1)
+ scm_syserror ("ftruncate");
+}
+
+static void
+fport_close (SCM port)
+{
+ scm_t_fport *fp = SCM_FSTREAM (port);
+
+ if (SCM_REVEALED (port) > 0)
+ /* The port has a non-zero revealed count, so don't close the
+ underlying file descriptor. */
+ return;
+
+ scm_run_fdes_finalizers (fp->fdes);
+ if (close (fp->fdes) != 0)
+ /* It's not useful to retry after EINTR, as the file descriptor is
+ in an undefined state. See http://lwn.net/Articles/365294/.
+ Instead just throw an error if close fails, trusting that the fd
+ was cleaned up. */
+ scm_syserror ("fport_close");
+}
+
+static int
+fport_random_access_p (SCM port)
+{
+ scm_t_fport *fp = SCM_FSTREAM (port);
+
+ if (fp->options & SCM_FPORT_OPTION_NOT_SEEKABLE)
+ return 0;
+
+ if (lseek (fp->fdes, 0, SEEK_CUR) == -1)
+ return 0;
+
+ return 1;
+}
+
+static int
+fport_wait_fd (SCM port)
+{
+ return SCM_FSTREAM (port)->fdes;
+}
+
+/* Query the OS to get the natural buffering for FPORT, if available. */
+static void
+fport_get_natural_buffer_sizes (SCM port, size_t *read_size, size_t *write_size)
+{
+#ifdef HAVE_STRUCT_STAT_ST_BLKSIZE
+ scm_t_fport *fp = SCM_FSTREAM (port);
+ struct stat st;
+
+ if (fstat (fp->fdes, &st) == 0)
+ *read_size = *write_size = st.st_blksize;
+#endif
+}
+
+static scm_t_port_type *
+scm_make_fptob ()
+{
+ scm_t_port_type *ptob = scm_make_port_type ("file", fport_read, fport_write);
+
+ scm_set_port_print (ptob, fport_print);
+ scm_set_port_needs_close_on_gc (ptob, 1);
+ scm_set_port_close (ptob, fport_close);
+ scm_set_port_seek (ptob, fport_seek);
+ scm_set_port_truncate (ptob, fport_truncate);
+ scm_set_port_read_wait_fd (ptob, fport_wait_fd);
+ scm_set_port_write_wait_fd (ptob, fport_wait_fd);
+ scm_set_port_input_waiting (ptob, fport_input_waiting);
+ scm_set_port_random_access_p (ptob, fport_random_access_p);
+ scm_set_port_get_natural_buffer_sizes (ptob, fport_get_natural_buffer_sizes);
+
+ return ptob;
+}
+
+/* We can't initialize the keywords from 'scm_init_fports', because
+ keywords haven't yet been initialized at that point. */
+void
+scm_init_fports_keywords ()
+{
+ k_guess_encoding = scm_from_latin1_keyword ("guess-encoding");
+ k_encoding = scm_from_latin1_keyword ("encoding");
+}
+
+static void
+scm_init_ice_9_fports (void)
+{
+#include "fports.x"
+}
+
+void
+scm_init_fports ()
+{
+ scm_file_port_type = scm_make_fptob ();
+
+ scm_c_register_extension ("libguile-" SCM_EFFECTIVE_VERSION,
+ "scm_init_ice_9_fports",
+ (scm_t_extension_init_func) scm_init_ice_9_fports,
+ NULL);
+
+ /* The following bindings are used early in boot-9.scm. */
+
+ /* Used by `include' and also by `file-exists?' if `stat' is
+ unavailable. */
+ scm_c_define_gsubr (s_scm_i_open_file, 2, 0, 1, (scm_t_subr) scm_i_open_file);
+
+ /* Used by `open-file.', also via C. */
+ sym_relative = scm_from_latin1_symbol ("relative");
+ sym_absolute = scm_from_latin1_symbol ("absolute");
+ sys_file_port_name_canonicalization = scm_make_fluid ();
+ scm_c_define ("%file-port-name-canonicalization",
+ sys_file_port_name_canonicalization);
+}